INS Arihant (ATV) Launch News and Discussion

Cybaru
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Re: INS Arihant (ATV) Launch News and Discussion

Postby Cybaru » 24 Jul 2009 22:12

3 nuke boats from zero aint that bad.

S1, S2 and Nerpa aint that bad. Thats a huge boost.

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Re: INS Arihant (ATV) Launch News and Discussion

Postby Drevin » 24 Jul 2009 22:19

prashanth wrote:



What about towed sonar array? Also the speed of submarine under surfaced and submerged conditions appears to be interchanged.

Added later: The India Today article is by far the most detailed article about our ATV.
Jai Hind. :D


Is this an official cut diagram or is it a virginia class sourced speculative diagram as mentioned?

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Re: INS Arihant (ATV) Launch News and Discussion

Postby Katare » 24 Jul 2009 22:37

S1's probably just a land based lab prototype/rig with a live nuclear reactor for research, testing and training, while S2 is real deployable stuff......

1.25 more days to go!

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Re: INS Arihant (ATV) Launch News and Discussion

Postby Vivek K » 24 Jul 2009 22:40

What would prevent that prototype from being pushed into the sea to test a few things?

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Re: INS Arihant (ATV) Launch News and Discussion

Postby ramana » 24 Jul 2009 22:49

The shore based one is used for training crews and research uses. So that would be curtailed.

Also IT article says that the vessel was floated on July 20th to check it out. So no need for heebies.

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Re: INS Arihant (ATV) Launch News and Discussion

Postby Arun_S » 24 Jul 2009 23:23

sunilUpa wrote:Original Sandeep Unnithan's article. Posting in full.

Deep Impact

Armed with nuclear tipped ballistic missiles (SLBMs), they form the third leg of a nation’s nuclear ‘triad’ comprising air and surface-launched nuclear weapons. Over the next five years, the troika of Arihant class SSBNs, each costing Rs 3,200 crore, will make the third leg of India’s nuclear triad—a strategic underwater platform for launching nuclear weapons.

.... .. The Indian private sector was chosen to build the 104-metre-long prototype, dubbed S2. Larsen&Toubro (L&T) built the hull, Tata Power made the control systems and Walchandnagar Industries made the complex high pressure pumps and valves which carried saturated steam. The BARC had still not succeeded in perfecting the reactor so the Government decided to continue reactor development parallel to the construction of the first submarine.

..... . . On January 5, 1998, in a quiet ceremony at the L&T’s Hazira facility, the then DRDO chief APJ Abdul Kalam symbolically cut the first steel plate of the ATV. The project picked up speed under the NDA and during the tenure of Atal Bihari Vajpayee, the prime minister who stunned the world by bringing India out of the nuclear closet. Vajpayee, who also headed the newly-established NCA, chaired the apex committee of the ATV.

The project also had two other authorities—the political and the executive council. The project remained under the direct control of Vajpayee through his national security adviser, Brajesh Mishra. Talks for the lease of another nuclear submarine with Russia were revived.

.... . . The project entered its last mile during Manmohan Singh’s first tenure in 2004. He attended several meetings and would often ask project officials, “Everything alright?” The query was a mere formality because the project received unstinted support. In 2005, the UPA Government gave an in-principle clearance for building a follow-on series of larger ballistic missile submarines (SSBNs), costing nearly Rs 8,000 crore a piece or nearly twice that of the current series of ATVs and another line of nuclear-powered fast attack submarines (SSNs) to escort them.:twisted:

So the 5000 tonne, 104 m x 10m, Rs 3,500 Crore/unit Arihant is the first operational mutifunctional nuclear powered sub that proves the foundation. It has 4 tubes for ballistic missiles (K15 and short version of A3SL).

The larger ballistic missile submarines (SSBNs), costing nearly Rs 8,000 crore a piece will be a classic boomer, of larger displacement and diameter for many more ballistic missiles each with longer range (a.k.a full version of A3SL)

And the third type of nuclear-powered fast attack submarines (SSNs) will likely be ~4000 tonne craft.

Jai Ho.

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Re: INS Arihant (ATV) Launch News and Discussion

Postby Rahul M » 24 Jul 2009 23:27

^^^
how different do you think those designs would be from this baby boomer design ?
just a larger one with another reactor for the boomer ?

I guess the SSN will be pretty similar, only the weapon sections will be different.

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Re: INS Arihant (ATV) Launch News and Discussion

Postby vijyeta » 24 Jul 2009 23:27

Is there any SOSUS or equivalent deployed in the IOR?

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Re: INS Arihant (ATV) Launch News and Discussion

Postby Rahul M » 24 Jul 2009 23:30

vijyeta wrote:Is there any SOSUS or equivalent deployed in the IOR?

even if it is we will certainly not discuss it.

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Re: INS Arihant (ATV) Launch News and Discussion

Postby csharma » 24 Jul 2009 23:37

Really reassuring to see the continuity in support. Much maligned MMS has also supported the program by sanctioning bigger SSBNs. This is a great moment for India as momentous as the nuclear tests.

Btw, how the hell did the Chinese get their first nuke submarine out in 1971? Russian help?

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Re: INS Arihant (ATV) Launch News and Discussion

Postby Lalmohan » 24 Jul 2009 23:50

csharma wrote:Really reassuring to see the continuity in support. Much maligned MMS has also supported the program by sanctioning bigger SSBNs. This is a great moment for India as momentous as the nuclear tests.

Btw, how the hell did the Chinese get their first nuke submarine out in 1971? Russian help?


check wiki, bit of info there. 1974 apparently, and mention of russian and french help to fix later rather than build

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Re: INS Arihant (ATV) Launch News and Discussion

Postby compved » 24 Jul 2009 23:53

Excellent news, however a range of 750kms wont do any good. We need to have atleast 7500km+ or do we already have em ?

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Re: INS Arihant (ATV) Launch News and Discussion

Postby Arun_S » 24 Jul 2009 23:57

Image
I found the speed information in this diagram is misleading/incorrect: The surface speed is listed as 25 knot and submerged is 22 Knot. Basic hydrodynamics will tell that this is impossible. The numbers are reversed, the correct numbers should be:
submerged speed 25 kt and
surface speed 22 kt.

As an aside the often quoted 130MW reactor is likely for the bigger boomer sub, and I think it is a fully native design.

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Re: INS Arihant (ATV) Launch News and Discussion

Postby Suraj » 25 Jul 2009 00:05

The Chinese program was authorized in 1958, as opposed to 1974 for the ATV program. They also followed a different approach - get a boat ready, however rudimentary the initial version, and continuously improve it. The Hans still retain a reputation of being very noisy boats. Our approach has been very different. Not only is the Arihant very technological complex to start with, but it is also our first attempt at building a submarine - any kind of submarine. The level of hidden political backing over the years for this project is just extraordinary; reading Sandeep Unnithan's latest missive was :eek:

Each new piece of information has indicated just how shrewd the Arihant design decisions were. This is not meant to be a final replicatable design. Instead, it will be a single prototype to test all manner of design options, from the hull shape to the submerged launching platform. The lessons from flogging the Arihant will then be incorporated in parallel into two flights of systems - the SSN and the SSB/GN lines. I would expect that we'll quickly ramp up our nuclear submarine count as the Arihant provides operational feedback, with the primary hurdle being scalability of manufacturing, since money appears to be not to be the primary impediment.

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Re: INS Arihant (ATV) Launch News and Discussion

Postby csharma » 25 Jul 2009 00:12

A simple question: Does the successful launch of Arihant mean that India can also build state of the art conventional submarines also? Seems like we are dependent on the French or other foreign suppliers for the diesel subs.

Or are there crucial technologies for conventional subs that need to be mastered?

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Re: INS Arihant (ATV) Launch News and Discussion

Postby Austin » 25 Jul 2009 00:12

Arun_S wrote: The numbers are reversed, the correct numbers should be:
submerged speed 25 kt and surface speed 22 kt.


The Tear Drop design should be more efficient and faster under water than on surface , so with the specs mentioned the displacement ,power and being a Charlie derivative , imho the surface speed should be 12 ~ 13 kt and submerged speed of 24 ~ 25 kt

BTW full marks to Sandeep for demystifying ATV , he should be on Headlines Today on Sunday in an interview with Shiv Aroor during the D day.
Last edited by Austin on 25 Jul 2009 00:17, edited 1 time in total.

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Re: INS Arihant (ATV) Launch News and Discussion

Postby putnanja » 25 Jul 2009 00:14

So is it a charlie class derivative or akula class derivative? And is it 80MWt?

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Re: INS Arihant (ATV) Launch News and Discussion

Postby Arun_S » 25 Jul 2009 00:22

Austin wrote:
Arun_S wrote: The numbers are reversed, the correct numbers should be:
submerged speed 25 kt and surface speed 22 kt.


The Tear Drop design should be more efficient and faster under water than on surface , so with the specs mentioned the displacement ,power and being a Charlie derivative , imho the surface speed should be 12 ~ 13 kt and submerged speed of 24 ~ 25 kt


Any craft on water surface is trapped in wake induced drag power loss (due to limited transversal speed of the wake) the drag is much higher than the laminary flow deeper below surface in longitudnal pressure regime.

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Re: INS Arihant (ATV) Launch News and Discussion

Postby Austin » 25 Jul 2009 00:23

RaviBg wrote:So is it a charlie class derivative or akula class derivative? And is it 80MWt?


Yes its modified Charlie design as per the report , its 80 MW(t) which should be ~ 15 -16 MW(e)

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Re: INS Arihant (ATV) Launch News and Discussion

Postby Austin » 25 Jul 2009 00:33

Arun_S wrote:Any craft on water surface is trapped in wake induced drag power loss (due to limited transversal speed of the wake) the drag is much higher than the laminary flow deeper below surface in longitudnal pressure regime.


Point taken , but a Tear Drop Design or a Albacore type would always be more efficient under water than on surface due to the drag factor that you have explained above.

Compared to a Foxtort or WW2 type design which are faster when on surface then submerged ?

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Re: INS Arihant (ATV) Launch News and Discussion

Postby Venkarl » 25 Jul 2009 00:34

That article gave me goosebumps :-o ...hats off to those who have done/still providing our nuke sub projects with political, financial, technological etc efforts....I am only looking forward for more and more strategic projects with strong infrastructure capabilities.

And Gurulog, why is that "S73" on the submarine? I see no connection with onondaga?

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Re: INS Arihant (ATV) Launch News and Discussion

Postby Suraj » 25 Jul 2009 00:36

Ajai Shukla on the Arihant in Business Standard. Note that I'm posting in full, because I'm not confident about BS's archiving system. Other mods - please truncate the posting if you think copyright concerns will be a problem:
Securing the Seas

India’s first nuclear-powered submarine marks the start of navy deployments and reforms that will catapult it into the league of serious maritime powers, reports Ajai Shukla.

One hallmark of some of the world’s path-breaking projects has been the choice of impressively lofty names. The first atomic bomb was built under Project Manhattan. Project Apollo put the first man on the moon. But for some reason, perhaps simply native modesty, one of India’s most challenging technological developments — its first nuclear-powered submarine — has been cloaked in blandness. When tomorrow morning, Prime Minister Manmohan Singh’s wife, Gursharan Kaur, breaks a coconut on the hull of what is referred to as the ATV or the Advanced Technology Vessel, to christen it INS Arihant, it will launch a new era for the navy.

With the christening, water will be let into the Vishakhapatnam dock called The Shipbuilding Centre, from where INS Arihant will begin its underwater journey. Once submerged, it will undergo two years of extensive trials, first in harbour and then at sea, before formally joining the navy.

The Arihant will not be alone. Two other boomers are under construction at L&T’s Hazira plant. These will probably be followed by more, equipped with longer-range nuclear-tipped missiles.

Senior naval planners explain the logic behind India’s rapid naval expansion. Other than the great naval powers — US, Russia and, now arguably, China — most major navies operate in alliance with one of the big players. Since the Cold War, for example, Britain’s royal navy has functioned in alliance with the US navy, specialising in anti-submarine warfare, and relying on US cover for crucial aspects like anti-air defence.

In contrast, India has always rejected military alliances. As a serving naval admiral elaborates, “India is different. We can operate for a short while as a partnership navy, but definitely not as part of a military alliance. We, therefore, need a balanced navy with all-round capability which can operate alone for as long as it takes.” But even while rejecting formal alliances, Indian navy admirals realise that to be taken seriously, a navy must be visible. That has spawned a series of annual exercises with foreign navies, including the Malabar series with the US Navy, the Varuna series with the French navy, the Konkan series with Britain’s royal navy, and the Indra series with the Russian navy. Early this year, India sent three warships to China for the 60th anniversary celebrations of its navy.

“It’s important to strut your stuff,” says a naval planner, “you visit a foreign port and invite your counterparts to a cocktail party on board. While sipping their drinks on the warship’s deck, they are taking note of the weaponry you’re carrying. You’re sending a clear message.”

Naval planners point to the historic link between trade and military power. An officer explained, “In the colonial period, it was said that ‘trade follows the flag’. Today, we see, as with China in Africa, the flag follows trade. But in no case can trade be divorced from the flag.” An indicator of the navy’s shift into the mainstream of Indian strategic planning — more so than the growing number of capital warships — is the growth in its command and administrative infrastructure. The deep-water Karwar naval base, located 34 nautical miles (55 km) south of Goa, is already functioning. Aimed at decongesting Mumbai, Karwar will be base for more than 40 ships, including the aircraft carrier Vikramaditya when it is commissioned.

Edited: Truncated post. Read entire article at the blog: Blog link
Last edited by Suraj on 26 Jul 2009 03:47, edited 2 times in total.
Reason: broken link fixed - it was missing the '/' at the end

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Re: INS Arihant (ATV) Launch News and Discussion

Postby ramana » 25 Jul 2009 00:42

He means 'bomber' = 'boomer'

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Re: INS Arihant (ATV) Launch News and Discussion

Postby Rahul M » 25 Jul 2009 00:43

suraj, it will appear on his blog tomorrow. you can cut it short without fears of archival.

edit : your fears about BS were well founded. the article is already not available !

He means 'bomber' = 'boomer'

bomber is the RN term for SSBNs.

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Re: INS Arihant (ATV) Launch News and Discussion

Postby Suraj » 25 Jul 2009 00:51

I will edit my post to truncate the text once his blog entry appears, and will add a pointer to the blog entry as well.\

Edited: done.

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Re: INS Arihant (ATV) Launch News and Discussion

Postby vijyeta » 25 Jul 2009 00:52

Suraj wrote:.......... So sensitive are today’s active sonars, and so skilled the sonar operators, that they can differentiate biological signals (whales, fish, even shrimp feeding) from the sounds coming from a submarine. ........
[/quote]

Active=passive

An active Sonar providing feedback on shrimp? :D
Maybe the feedback will be from the shrimp writhing in agony from an active sonar blast.....

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Re: INS Arihant (ATV) Launch News and Discussion

Postby Anujan » 25 Jul 2009 00:54

I learned a lot from this document. I encourage Rakshaks to atleast skim it.
Some Aspects of Submarine Design: Part 1. Hydrodynamics (PDF Link)

The history of submarines shows there were two significant advances in the performance of submarines, which occurred after full scientific studies were undertaken. The first was by theGermans at the end of World War II when they produced the Type 21, which could have upset the balance in the U-Boat campaign if it had arrived earlier. The second was by the US Navy with Albacore which had a submerged speed of over 30 knots. To neglect full scientific studies would be a serious mistake in the design of any future replacement submarine. Design is shown to be like a jigsaw puzzle where altering one piece requires alterations in all surrounding features to make a workable complete design. The basis of improved hydrodynamic features is discussed. A new nose shape is presented which should improve the performance of the forward passive sonar up to operational speeds. Other major sources of resistance may be improved. It is proposed a first major step should be to establish the detailed performance of Collins uing wind tunnels and computational fluid dynamics which will serve as the comparative foundation for any new design.

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Re: INS Arihant (ATV) Launch News and Discussion

Postby negi » 25 Jul 2009 00:58

To be honest we cannot compare the weapons platform acquisition and development curve for India and China ; infact in terms of military and nuclear technology China got a lot of freebies and a large scale IP sharing from RU during right from 50's onwards (their first nukes,ss-18 technology,Mig-21 manufacturing ,scuds,T-55's etc etc) pretty much on the lines of munna UKstan being spoon fed by Unkil when it came to strategic weapons.

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Re: INS Arihant (ATV) Launch News and Discussion

Postby Cybaru » 25 Jul 2009 01:03

Arun_S wrote:And the third type of nuclear-powered fast attack submarines (SSNs) will likely be ~4000 tonne craft.

Jai Ho.


Scorpene XXL or aka Barracuda is also 4100 tons..

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Re: INS Arihant (ATV) Launch News and Discussion

Postby Suraj » 25 Jul 2009 01:07

Note that Ajai Shukla mentions the acquisition of two Akula SSNs, while Sandeep Unnithan claims only one will be acquired...

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Re: INS Arihant (ATV) Launch News and Discussion

Postby Arun_S » 25 Jul 2009 01:20

My sources said three Chakra's (Akula) are coming. :wink:

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Re: INS Arihant (ATV) Launch News and Discussion

Postby vasu_ray » 25 Jul 2009 01:21

a) These planned attack SSNs, if they trail Chinese SSBNs can do boost phase interception of SLBMs? even if they aren't actively trailing, after the first SLBM launch say 100kms away, can these SSNs react to intercept subsequent launches?

b) At the outset of hostilities, if a preemptive attack on a SSBN results in a ripple launch of nuke missiles on pre selected
targets (in a use it or lose it scenario), wouldn't that result in crossing the nuclear threshold pretty quickly? the worry is 'an incident' spiraling into nuclear war

the recent Chinese anti-sub war gaming report leaked as a real incident gives me the real frets, their cocky nature can be a trigger unless correct 'expectations' are set

Anyways an unintended benefit is that the 8000cr product series is driving a Eco system of companies in the Indian economy

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Re: INS Arihant (ATV) Launch News and Discussion

Postby Anant » 25 Jul 2009 02:22

This is a submarine, specifically the USS Jimmy Carter, undergoing magnetic silencing. I am assuming our boat undergoes or will undergo something similar. I just got me a 6 pack of Indian beer (here in the USA). Party time this weekend. Jai Hind and hearty congrats to all of us, Indians, world wide.

http://img137.imageshack.us/img137/125/zkl5.jpg

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Re: INS Arihant (ATV) Launch News and Discussion

Postby SRay » 25 Jul 2009 03:23

Anant wrote:This is a submarine, specifically the USS Jimmy Carter, undergoing magnetic silencing....


FWIW, there is an interesting history to the magnetic degaussing of ships:
http://en.wikipedia.org/wiki/Degaussing#Degaussing_ship.27s_hulls

Do modern battleships/submarines use this still?

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Re: INS Arihant (ATV) Launch News and Discussion

Postby Anant » 25 Jul 2009 03:34

SRay,

Yes they do. The Jimmy Carter (in the photo) is still in active service and was launched in 2004. Thanks!

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Re: INS Arihant (ATV) Launch News and Discussion

Postby Anant » 25 Jul 2009 03:42

SRay,

I guess in the context of submarines and other vessels (Degaussing) is known as deperming. Check out:

http://en.wikipedia.org/wiki/Deperming

The US of course even named one ship the USS DePerm :rotfl:

And apparently there are differences between deperming and degaussing. Check out:

http://tinyurl.com/mepykj

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Re: INS Arihant (ATV) Launch News and Discussion

Postby Gagan » 25 Jul 2009 05:20

Everyone missed this article again by Sandip Unnithan. The headline sounds too good to be true, and this is Sandip we are talking about. But read on and :cry: truth becomes evident.

But isn't the Rubis class a "N-powered scorpene" effectively?

Scorpene N-sub delivery gets delayed
Scorpene N-sub delivery gets delayed
Sandeep Unnithan
New Delhi, July 20, 2009
Even as India readies to launch its first nuclear-powered submarine on July 26, Defence Minister A.K. Antony admitted that construction of the Scorpene class conventional submarines was delayed.
...
India signed a multi-billion dollar contract with French firm Armaris in 2005 for the construction of six Scorpene class diesel-electric submarines. Construction of the first, second and third submarine commenced in December 2006, December 2007 and August 2008 respectively. As per the contract signed with Mazagaon Docks Limited (MDL), the first submarine is scheduled to be delivered in December 2012 and thereafter, one each every year till December 2017.
...
India's ageing submarine fleet has not added a new submarine for close to a decade and the fleet is in danger of shrinking to less than half the present strength of 16 submarines over the next decade.

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Re: INS Arihant (ATV) Launch News and Discussion

Postby vina » 25 Jul 2009 05:50

Any craft on water surface is trapped in wake induced drag power loss (due to limited transversal speed of the wake) the drag is much higher than the laminary flow deeper below surface in longitudnal pressure regime


El Senor es faulto. What happens is that there are two components of resistance in a surface ship, the wave making drag and the skin friction drag. Fundamentally it is because there is an air-water boundary which the surface ship operates on. So when it has to spend energy making waves . The waves are basically just gravity waves, not very different from that fundamentally created by wind over open waters (the difference being that the water is lifted up at the bow and stern by the ships movement in this case, but the rest of the stuff is similar). The energy expended in creating these waves show up as wave making resistance and you use the same Froude Number to estimate that like you would to do with open waves as well. In addition to the wave making resistence, you have the "skin resistance" as well, which adds to the wave making resistance

Now coming to a submarine traveling underwater, there is no air/water boundary (gravity waves simply die out rapidly and have close to zero effect at depths greater than the maybe twice the height of the wave.. even in hurricane like gale at a depth of 10 meters or so, there will be absolutely no effect and so a submarine under water will not get tossed about like a surface ship would in a gale). So the only source of drag is the skin friction drag ..

So you can see that for a ship of exactly same total wetted surface as the submarine , in addition to the skin friction drag (which will be exactly the same for the two, assuming same materials fineness ratio etc), there is the ADDITIONAL energy expended in making the surface waves.

In plain Inglees , the submarine travels faster because there are no waves under water and so no energy is spent making waves!. Zimble onree , no ? :wink:

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Re: INS Arihant (ATV) Launch News and Discussion

Postby vina » 25 Jul 2009 06:22

Image

Hmm. So my final guesses was spot on with displacement of 5000 tons, and length of 110 was very close and breadth of 10m was spot on.

So this is what I had posted earlier , right in the first page before bringing down the weight estimate to 5000 tons.
    ength = 110m ( a 8 m stretch)
    Breadth = 10 m (largely same as Charlie II)
    Displacement = 6000 tons submerged ( assuming Agni III SL is 50 tons at launch , so diff of 600 tons over Charlie II)
    Block Coeff = 0.6618 (same as Charlie II)
    Reactor = 1 nos PWR of around 150 MW
    Turbine = 1 nos
    Shaft = 1 nos
    Speed = 26 Max (submerged)
    = 16 Max (surfaced)
    Silent speed = 10 knots max.
    Design depth = 300m
    Missile Firing Depth = 60m to 75m or so I would think

So I think finally the ATV will be like this.
    length = 104m
    Breadth = 10 m (largely same as Charlie II)
    Displacement = 5000 tons submerged
    Block Coeff = 0.4807 (Significantly less than Charlie II at 0.53xx)
    Reactor = 1 nos PWR of around 90 MW
    Turbine = 1 nos (Charlie II has two turbines, but one shaft. But the Arihant has 5000 shp more , but strongly believe Yindoo boat will have only one turbine)
    Shaft = 1 nos
    Speed = 26 Max (maybe 30 submerged , if the 5000 hp more over the Charlie II is true)
    = 21 Max (surfaced , ok max 23-24 , I doubt more than that , because of the increased fineness ratio over the charlie II)
    Silent speed = 10 knots max.
    Design depth = 300m (safe depth 450m, never exceed 600m)
    Missile Firing Depth = 60m or so I would think

Somehow doubt the cunning yindoos. There must be a couple of tons of concrete ballast on that boat right now to allow for the growth in weight for bigger missiles.. So K-X sounds credible.. Maybe a "tarrel than mountain" missile when compared to K-15 with similar diameter ?

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Re: INS Arihant (ATV) Launch News and Discussion

Postby vina » 25 Jul 2009 06:25

Good article Arun_S. Maybe you could put a link on that in the BRF page somewhere if it is too painful to make it into HTML.

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